Translation of an existing implantable cardiac monitoring device for measurement of gastric electrical slow-wave activity

BackgroundDespite evidence that slow-wave dysrhythmia in the stomach is associated with clinical conditions such as gastroparesis and functional dyspepsia, there is still no widely available device for long-term monitoring of gastric electrical signals. Actionable biomarkers of gastrointestinal health are critically needed, and an implantable slow-wave monitoring device could aid in the establishment of causal relationships between symptoms and gastric electrophysiology. Recent developments in the area of wireless implantable gastric monitors demonstrate potential, but additional work and validation are required before this potential can be realized.MethodsWe hypothesized that translating an existing implantable cardiac monitoring device, the Reveal LINQ (TM) (Medtronic), would present a more immediate solution. Following ethical approval and laparotomy in anesthetized pigs (n = 7), a Reveal LINQ was placed on the serosal surface of the stomach, immediately adjacent to a validated flexible-printed-circuit (FPC) electrical mapping array. Data were recorded for periods of 7.5 min, and the resultant signal characteristics from the FPC array and Reveal LINQ were compared.Key ResultsThe Reveal LINQ device recorded slow waves in 6/7 subjects with a comparable period (p = 0.69), signal-to-noise ratio (p = 0.58), and downstroke width (p = 0.98) to the FPC, but with reduced amplitude (p = 0.024). Qualitatively, the Reveal LINQ slow-wave signal lacked the prolonged repolarization phase present in the FPC signals.Conclusions & InferencesThese findings suggest that existing cardiac monitors may offer an efficient solution for the long-term monitoring of slow waves. Translation toward implantation now awaits. An existing implantable cardiac monitor (Reveal LINQ) was placed next to a validated extracellular electrical recording device (FPC array) on the serosal surface of a pig stomach. The recorded signals from these devices had comparable periods and signal-to-noise ratios. Existing cardiac monitors may offer a solution for the long-term monitoring of gastric slow-wave frequency.image